Several aspects of the proposal, which aims to expand open access, require serious discussion and, in some cases, a rethink.
Image credit: Dave Cutler (artist).
New Research In
Physical Sciences
Featured Portals
Articles by Topic
Biological Sciences
Featured Portals
Articles by Topic
Contributed by Hans Clevers, May 15, 2018 (sent for review April 13, 2018; reviewed by Pei-Jer Chen and Bernard Roizman)
Significance
Influenza virus infection represents a major threat to public health worldwide. There is no biologically relevant, reproducible, and readily available in vitro model for predicting the infectivity of influenza viruses in humans. Based on the long-term expanding 3D human airway organoids, we developed proximal differentiation and further established a 2D monolayer culture of airway organoids. The resultant 3D and 2D proximal differentiated airway organoids can morphologically and functionally simulate human airway epithelium and as a proof of concept can discriminate human-infective influenza viruses from poorly human-infective viruses. Thus, the proximal differentiated airway organoids can be utilized to predict the infectivity of influenza viruses and, more broadly, provide a universal platform for studying the biology and pathology of the human airway.
Abstract
Novel reassortant avian influenza H7N9 virus and pandemic 2009 H1N1 (H1N1pdm) virus cause human infections, while avian H7N2 and swine H1N1 virus mainly infect birds and pigs, respectively. There is no robust in vitro model for assessing the infectivity of emerging viruses in humans. Based on a recently established method, we generated long-term expanding 3D human airway organoids which accommodate four types of airway epithelial cells: ciliated, goblet, club, and basal cells. We report differentiation conditions which increase ciliated cell numbers to a nearly physiological level with synchronously beating cilia readily discernible in every organoid. In addition, the differentiation conditions induce elevated levels of serine proteases, which are essential for productive infection of human influenza viruses and low-pathogenic avian influenza viruses. We also established improved 2D monolayer culture conditions for the differentiated airway organoids. To demonstrate the ability of differentiated airway organoids to identify human-infective virus, 3D and 2D differentiated airway organoids are applied to evaluate two pairs of viruses with known distinct infectivity in humans, H7N9/Ah versus H7N2 and H1N1pdm versus an H1N1 strain isolated from swine (H1N1sw). The human-infective H7N9/Ah virus replicated more robustly than the poorly human-infective H7N2 virus; the highly human-infective H1N1pdm virus replicated to a higher titer than the counterpart H1N1sw. Collectively, we developed differentiated human airway organoids which can morphologically and functionally simulate human airway epithelium. These differentiated airway organoids can be applied for rapid assessment of the infectivity of emerging respiratory viruses to human.
Footnotes
↵1J.Z., C.L., and N.S. contributed equally to this work.
↵2H. Clevers and K.-Y.Y. contributed equally to this work.
- ↵3To whom correspondence may be addressed. Email: h.clevers{at}hubrecht.eu or kyyuen{at}hku.hk.
Author contributions: J.Z., H. Chen, H. Clevers, and K.-Y.Y. designed research; J.Z., C.L., M.C.C., B.H.-Y.W., H. Chu, V.K.-M.P., D.W., X.Z., L.W., W.S., S.Y., and K.K.-Y.W. performed research; N.S. and H. Clevers contributed new reagents/analytic tools; J.Z., C.L., M.C.C., B.H.-Y.W., H. Chu, J.F.-W.C., K.K.-W.T., H. Chen, and K.-Y.Y. analyzed data; and J.Z., H. Chen, H. Clevers, and K.-Y.Y. wrote the paper.
Reviewers: P.-J.C., Graduate Institute of Clinical Medicine; and B.R., The University of Chicago and Shenzhen International Institute for Biomedical Research.
The authors declare no conflict of interest.
Data deposition: The sequences reported in this paper have been deposited in the GenBank database [A/swine/Guangdong/07 HA (H1N1sw) accession no. MH293472 and Avian H7N2 HA (A/pigeon/Zhejiang/DTID-ZJU01/1-1/2013) accession no. MH186147].
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1806308115/-/DCSupplemental.
- Copyright © 2018 the Author(s). Published by PNAS.
This open access article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND).
Differentiated human airway organoids to assess infectivity of emerging influenza virus
Sign up for Article Alerts
Jump to section
You May Also be Interested in
Several large or long-lived animals seem strangely resistant to developing cancer. Elucidating the reasons why could lead to promising cancer-fighting strategies in humans.
Image credit: Shutterstock.com/ronnybas frimages.
PNAS Profile of NAS member and biochemist Hao Wu
A study suggests a putative gene-expression hallmark common to monogamous male vertebrates of some species, namely cichlid fishes, dendrobatid frogs, passeroid songbirds, common voles, and deer mice, and identifies 24 candidate genes potentially associated with monogamy.
Image courtesy of Yusan Yang (University of Pittsburgh, Pittsburgh).
Physical and social well-being in old age are linked to self-assessments of life worth, and a spectrum of behavioral, economic, health, and social variables may influence whether aging individuals believe they are leading meaningful lives.
Image courtesy of Pixabay/MabelAmber.